Rinse the sabudana pearls 2 times in water to remove excess starch. Soak them in enough water to submerge for at least 4-5 hours, or overnight. This is the most crucial step! Soaking ensures the sabudana pearls cook evenly and become soft without clumping.
Later, transfer soaked sabudana to a colander. Rinse thoroughly with running water to get rid of all the starch. Let it sit on colander while the milk is simmering and all the water drains out.
Bring the milk to a gentle boil, then reduce the heat to low. Add cardamom powder, and half of soaked saffron.
Simmer the milk over lowest heat setting, stirring regularly to prevent from burning. After 15 minutes or so, the milk will start thickening, forming a layer of cream (rabdi), and turning pale yellow.
Once milk is reduced almost to half of the original quanity, add rinsed sabudana pearls and stir to evenly combine. Continue to cook the kheer over low heat till sabudana pearls are cooked. This take 10 – 15 minutes.
Once the kheer has reached a creamy consistency, add the sugar. Stir well until the sugar dissolves completely. Taste and adjust the sweetness as needed.
In a small pan, heat a tablespoon of ghee.Add the chopped nuts and roast them until they are lightly golden. Add the raisins and cook for another 30 seconds until they plump up.
Garnish the sabudana kheer with remaining soaked saffron and toasted nuts. You can serve the kheer warm or chilled.